STIX has only 1 science acquisition mode, which is independent from solar activity, campaigns, etc.
Data acquisition operations onboard do change based on the incoming flux. The attenuator is automatically used during high solar activity to suppress the count rates, cadence can be changed too.
STIX does change the data processing and packaging onboard, based on solar activity and automatic event detection:
During non-flaring times: STIX FPGA accumulates background counts for energy calibration.
- STIX may autonomously change attenuator and/or enable selective pixel suppression using predefined count rate criteria.
- STIX transmits flare flag message to s/c.
- In real time: STIX FPGA converts fine native A/D channels into detector-matched ‘science energy channels’.
- In real time: data are accumulated as a function of science energy channel, pixel and time bins (0.1 second or larger depending on statistics).
- In background (using pre-parameterized algorithms or in response to TC): STIX selects and compresses data in archive memory into TM-ready packets in the 'to be transmitted’ buffer.
When requested through TC: extra TM-ready packets can be selected and transferred to the SSMM for downlink.
STX_NORMAL with parameter DATARATE = 600 [bits/sec]